Systems and methods for controlling motion of detectors having moving detector heads

Abstract

An imaging system is provided including a gantry, a detector unit mounted to the gantry, at least one processing unit, and a controller. The at least one processing unit is configured to obtain object information corresponding to an object, and to automatically determine at least one first portion of the object and at least one second portion of the object. The controller is configured to control a rotational movement of the detector unit. The detector unit is rotatable at a sweep rate over a range of view of the object to be imaged, and the controller is configured to rotate the detector unit at an uneven sweep rate. The uneven sweep rate varies during the rotation from the, wherein a larger amount of scanning information is obtained for the at least one first portion than for the at least one second portion.

What is claimed is: 
     
       1. An imaging system comprising:
 a gantry; 
 a detector unit mounted to the gantry; 
 at least one processing unit configured to obtain object information corresponding to an object to be imaged, and to automatically determine, based on the object information, at least one first portion of the object and at least one second portion of the object, wherein the at least one first portion corresponds to a volume of interest having greater clinical interest than the at least one second portion, and the at least one second portion corresponds to a volume of lesser interest having lesser clinical interest than the at least one first portion; and 
 a controller configured to control a rotational movement of the detector unit used to acquire scanning information by detecting emissions from the object, wherein the controller rotates the detector unit at a sweep rate from a first position to a second position defining a range of view of the object to be imaged, wherein the controller rotates the detector unit from the first position to the second position at an uneven sweep rate during acquisition of the scanning information, the uneven sweep rate determined based on the determined at least one first portion and at least one second portion to vary during the rotation from the first position to the second position wherein a larger amount of the scanning information is obtained for the at least one first portion than for the at least one second portion based on the greater clinical interest of the first portion. 
 
     
     
       2. The imaging system of  claim 1 , wherein the detector unit is disposed on a detector carrier, wherein the detector rotates independently of the gantry in a direction transverse to a direction along which a patient is advanced into a bore of the gantry. 
     
     
       3. The imaging system of  claim 1 , wherein the controller is configured to rotate the detector unit continuously, and wherein the controller is configured to vary the sweep rate by varying a rotational speed at which the detector is rotated at different positions during the rotation of the detector unit. 
     
     
       4. The imaging system of  claim 1 , wherein the controller is configured to rotate the detector unit in a series of discrete steps, and wherein the controller is configured to vary the sweep rate by varying a time spent at the discrete steps. 
     
     
       5. The imaging system of  claim 1 , wherein the at least one first portion is determined using information from a Computed Tomography (CT) scan. 
     
     
       6. The imaging system of  claim 1 , wherein the at least one first portion is determined using a patient atlas. 
     
     
       7. The imaging system of  claim 1 , further comprising a collimator coupled to the detector unit, the detector unit comprising a pixel, the collimator having plural collimator bores corresponding to the pixel, the collimator including interior septa disposed above an internal portion of the pixel and exterior septa disposed above a border of the pixel, wherein the exterior septa have a greater wall thickness than the interior septa. 
     
     
       8. The imaging system of  claim 1 , further comprising a collimator coupled to the detector unit, the detector unit comprising a pixel, the collimator having plural collimator bores corresponding to the pixel, the collimator including interior septa disposed above an internal portion of the pixel and exterior septa disposed above a border of the pixel, wherein the exterior septa extend along a length from a top to a bottom of the collimator, wherein the interior septa do not extend to the top or the bottom of the collimator. 
     
     
       9. The imaging system of  claim 1 , wherein the gantry is rotated between different angular positions at the uneven sweep rate, wherein the detector unit rotates with the gantry, and wherein the sweep rate is different for at least two of the angular positions. 
     
     
       10. An imaging system comprising
 a gantry; 
 a plurality of detector units mounted to the gantry, the plurality of detector units individually movable including translational movement and rotational movement; 
 at least one processing unit configured to obtain object information corresponding to an object to be imaged, and to automatically determine, based on the object information, at least one first portion of the object and at least one second portion of the object, wherein the at least one first portion corresponds to a volume of interest having greater clinical interest than the at least one second portion, and the at least one second portion corresponds to a volume of lesser interest having lesser clinical interest than the at least one first portion; and 
 a controller configured to control the rotational movement of the plurality of detector units used to acquire scanning information by detecting emissions from the object, wherein the controller rotates the detector units from corresponding first positions to second positions defining a range of view of an object to be imaged, wherein the controller rotates at least one detector unit from the first position of the detector unit to the second position of the detector unit at an uneven sweep rate during acquisition of the scanning information, the uneven sweep rate determined based on the determined at least one first portion and the determined at least one second portion to vary during the rotation from the first position to the second position wherein a larger amount of the scanning information is obtained for the at least one first portion than for the at least one second portion based on the greater clinical interest of the first portion. 
 
     
     
       11. The imaging system of  claim 10 , wherein the controller is configured to rotate the at least one detector unit continuously, and wherein the controller is configured to vary the sweep rate by varying a rotational speed at which the at least one detector unit is rotated at different positions during the rotation of the at least one of the detector units. 
     
     
       12. The imaging system of  claim 10 , wherein the controller is configured to rotate the at least one detector units in a series of discrete steps, and wherein the controller is configured to vary the sweep rate by varying at a time spent at the discrete steps. 
     
     
       13. The imaging system of  claim 10 , wherein the at least one first portion is determined using information from a Computed Tomography (CT) scan. 
     
     
       14. The imaging system of  claim 10 , wherein the at least one first portion is determined using a patient atlas. 
     
     
       15. The imaging system of  claim 10 , wherein the controller is configured to control at least two of the plurality of detector units at different uneven sweep rates. 
     
     
       16. The imaging system of  claim 10 , further comprising a collimator coupled to the at least one detector unit, the at least one detector unit comprising a pixel, the collimator having plural collimator bores corresponding to the pixel, the collimator including interior septa disposed above an internal portion of the pixel and exterior septa disposed above a border of the pixel, wherein the exterior septa have at least one of a greater wall thickness than the interior septa or a greater length than the interior septa. 
     
     
       17. A method comprising:
 obtaining, with a processing unit, object information corresponding to an object to be imaged; 
 determining, automatically with the processing unit, based on the object information, at least one first portion of the object and at least one second portion of the object based on diagnostic interest of the one first portion and the second portion, wherein the at least one first portion corresponds to a volume of interest having greater clinical interest than the at least one second portion, and the at least one second portion corresponds to a volume of lesser interest having lesser clinical interest than the at least one first portion; 
 rotating at least one detector unit at a sweep rate from a first position to a second position defining a range of view of the object to be imaged to acquire scanning information by detecting emissions from the object, wherein rotating the detector unit comprises varying the sweep rate during the rotation from the first position to the second position during acquisition of the scanning information at an uneven sweep rate determined based on the determined at least one first portion and the determined at least one second portion, wherein a larger amount of scanning information is obtained for the at least one first portion than for the at least one second portion based on the greater clinical interest of the first portion. 
 
     
     
       18. The method of  claim 17 , wherein the obtaining object information includes performing a Computed Tomography (CT) scan, wherein the at least one first portion and the at least one second portion are determined using information from the CT scan. 
     
     
       19. The method of  claim 17 , wherein the at least one first portion is determined using a patient atlas. 
     
     
       20. The method of  claim 17 , wherein the detector unit is rotated substantially continuously and the varying the sweep rate comprises varying a rotational speed at which the at least one detector unit is rotated at different positions during the rotation of the at least one of the detector units. 
     
     
       21. The method of  claim 17 , wherein the detector unit is rotated in a series of discrete steps and the varying the sweep rate comprises varying a time spent at the discrete steps. 
     
     
       22. The method of  claim 17 , wherein the at least one detector unit comprises a first detector unit and a second detector unit, the method further comprising controlling the first detector unit and the second detector unit to rotate at different uneven sweep rates. 
     
     
       23. The method of  claim 17 , wherein the sweep rate is varied based on an identified portion being imaged of the object.